this is a hard 1

Last month I found out I was pregnant but then I had a miscarriage  4 days after my periods was due on that day al my levels was right bk down to none pregnant at the hospital! Now my app has recalculated everything I bled for 3 days them we got straight bk into it ! Now from my ovulation this month after the bleeding now says am due on 12days after my ovulation but normal it's 15 days after ovulation ! So don't no wen to test as am due on tomorrow and last month my positive was 14povulation if that makes sense am 11dpo now